Flush toilets

ABSTRACT

A toilet comprises a pan, a trap which normally retains water as a gas seal, and an outlet. The trap is arranged for movement, during flushing of the toilet, in a manner which causes the retained water to transfer by gravity to the outlet. In one aspect, the trap comprises a length of flexible hose having a curved portion which retains water as the gas seal.

INTRODUCTION

[0001] This invention relates to toilets with improved flushing arrangements. There is increasing pressure to reduce usage of water, even in areas such as the UK which have relatively high rainfall. One area of interest for reducing water consumption is the flushing of toilets, but this must be balanced against requirements of hygiene.

[0002] All current flush toilets use water for two separate purposes, namely the removal of waste matter from the toilet pan and the provision of a seal against escapes of sewer gas into buildings. This second purpose determines the minimum volume of water required for any remotely conventional toilet to function. But much more water is currently used. This is because part of it is needed to impart sufficient kinetic energy to swimming waste matter to force it round the trap.

STATEMENTS OF INVENTION

[0003] According to the present invention, a toilet includes a pan, a trap which normally retains water as a gas seal, and an outlet; and the trap is arranged for movement, during flushing of the toilet, in a manner which causes said retained water to transfer by gravity to the outlet.

[0004] The trap, in some forms of the invention, is a rigid conduit arranged for rotary or pivotal movement. In other forms, the trap is constituted by a length of flexible hose. The hose may normally form a curve in which said water is retained and be straightened during flushing by relative movement between the pan and the outlet. The trap generally takes the form of a continuous conduit connecting the pan and the outlet and is designed to hold a body of water between flushes, which body acts as a gas seal.

[0005] The trap is preferably moved by means linked to the flushing mechanism of an associated cistern. Said flushing mechanism may be a conventional siphon or, more preferably, a bell mechanism of known type. Alternatively the flushing mechanism may comprise a flexible hose having a partial loop which is moved to initiate flushing. Preferably, the arrangement is such that the initiation of flushing causes cleaning water to be supplied to the pan before or while movement of the trap commences.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the objects, advantages, and principles of the invention.

[0007]FIG. 1 shows a vertical section of a slightly modified flush toilet.

[0008]FIG. 2 shows one embodiment of a link with the flushing mechanism.

[0009]FIG. 3 shows a toilet where a trap makes use of flexible hose.

[0010]FIG. 4 is a front view of the relevant parts of the flushing system.

[0011]FIG. 5 shows a main ring with a number of smaller rings which can rotate on the main ring.

[0012]FIG. 6 shows one embodiment of an attachment of a hose pipe to a cistern and an overflow, and an attachment to a toilet pan.

[0013]FIG. 7 illustrates a managed trap.

[0014]FIG. 8 illustrates an immobile trap management pipe relative to a toilet pan.

[0015]FIG. 9 shows a toilet where a trap makes use of a short section of a pipe.

[0016]FIG. 10 shows flanges which securely seal connection of a hose with a toilet pan.

DETAILED DESCRIPTION OF THE INVENTION

[0017] The embodiment shown in FIGS. 1 and 2 uses a mechanical trap in conjunction with an immobile toilet pan.

[0018]FIG. 1 shows a vertical section through relevant parts of a slightly modified flush toilet. The toilet pan 1 terminates more or less horizontally. There would actually be functional advantages in pointing downwards at a small angle (say 5°). It is linked to the trap management pipe 2 which empties into the pipe 3 leading to the drains. The seals 4 at both ends of the trap management pipe 2 allow said trap management pipe 2 to rotate slightly (45° will be sufficient) relative to the toilet pan I and the pipe 3.

[0019]FIG. 2 shows one implementation of a possible link with the flushing mechanism. It represents a view, from the front, of all relevant components installed behind the toilet. The trap management pipe 2 is shown in a position 45% inclined against the vertical. This could be its normal position when the toilet is not in use. A user flushing the toilet would push down the lever 7, which is hinged at point 11. This pushes down the link 6 pressing the trap management pipe 2 to the floor. Once that has happened the water in the trap can flow to the drains without further impediments, carrying any waste matter with it. Once the lever 7 is released the spring 10 which is anchored to the floor or other parts of the whole mechanism, pulling on the lever 5 returns the trap management pipe 2 to its rest position.

[0020] Flushing can be achieved by an additional direct link from the lever 7; for example, the spindle of a conventional flushing mechanism could be linked to the lever at 11. But preferably a spring 9 could operate a wire pull 8 to trigger the flush. A traditional type flushing bell would probably work better than a syphon, because the flush can be initiated faster as the bell does not need to be held in its trigger position as long as a syphon.

[0021] To preserve an acceptable appearance for the whole assembly the entire mechanism, apart from the lever 7, would typically be enclosed in a box.

[0022] Instead of making the seals 4 watertight one could have a durable flexible hose pipe extending from the toilet pan 1 all the way through the bend in pipe 3. The trap management pipe 2 would then merely guide the hose pipe through the positions required for its function.

[0023]FIG. 3 illustrates a toilet where the trap makes use of flexible hose which undergoes bending, rather than twisting, motion.

[0024] The toilet pan 1 is linked to the trap management hose 12 at the immobile seal 14. The pan is held at the sides by sliding tracks 13 which allow it to be moved forward and upward in a frame (not shown), that is fixed to the floor. Preferably, the moving parts have an integrated back rest 18. If any toilet lid is fitted this back rest 18 ensures that when the pan is moved in its frame the lid does not tilt further backwards, sliding down the front of the cistern and possible becoming trapped below it. To slide the toilet pan one would typically pull at one of the handles 15. One such handle is preferably incorporated at the top of the backrest 18 in a position convenient for adult users. A second handle, for example below the front of the toilet pan, can be provided for children.

[0025] The pulling action straightens the trap management hose 12 and lifts the water trapped in the area of the seals 14 to a height from which it can flow to the drains without further impediment.

[0026] The balance between forward and upward motion of the toilet pan 1 is determined by the length of the hose 12 and the height to which the pan 1 must be lifted to achieve free flow water and waste.

[0027] Various mechanical means can be employed to ensure that the waste management pipe 12 is confined to shapes acceptable for the operation of the toilet. One of these methods could be prevention of sideways motion relative to the toilet by confinement between two vertical parallel plates (not shown).

[0028] As in the implementation described in FIGS. 1 and 2, this different design allows a direct mechanical link to the flushing mechanism. One such link is shown in FIG. 3. Again, a wire pull 8 is pulled via a spring 9. The roller 17, connected with a wall or the cistern, changes the direction of the pulling force. Alternatively, a Bowden cable could be used. In this implementation, as described in FIGS. 1 and 2, a flushing bell is preferable to a syphon.

[0029] Because the toilet pan moves relative to the cistern the water used in flushing has to travel through another hose pipe 17, from which it enters the pan at 16. The upper part of the pan can have the same shape as a conventional toilet, directing water to all parts of the pan.

[0030] Because a hose pipe 17 is used between the cistern and the toilet pan the method for flushing can be simplified. The wire pull 8, spring 9 and roller 17 can be dispensed with, as can the flushing bell or syphon in the cistern. Instead, the flush can be controlled by the hose pipe 17 itself.

[0031] Details of one way of achieving this are shown in FIG. 4, which shows only the relevant parts of the total assembly from the front.

[0032] The cistern 19 does not contain mechanical devices for flushing at all. Instead, the hose pipe 17 is attached to the cistern at the bottom of the latter. There is always water in the hose pipe. But the section of the hose pipe closest to the cistern is normally held up beyond the height of the entrance to the overflow pipe 20 of the cistern 19. In the implementation shown in FIG. 4 the hose pipe can move freely through the ring 21 which is shown more closely in FIG. 5 where one can see the main ring 21 with a number of smaller rings 29 rotating on it. Returning to FIG. 4, we see that the ring 21 is attached to a lever 22 which is hinged at point 25. A spring 23 attached at point 24 normally holds up the lever and thus the hose pipe 17. When the toilet pan is moved forward and upward the hose pipe 17 is pulled by the same action. This allows the cistern to be drained through the hose pipe. As in traditional flushing mechanisms the hose pipe acts as a syphon once enough water has passed its highest point.

[0033] Further rings like the ring 21 can be employed along the path of the hose pipe 17 to ensure smooth operation of the mechanism. To preserve an acceptable appearance of the whole assembly, substantially the whole flushing mechanism would typically be enclosed in a box.

[0034] In some parts of the world there may be regulatory objections to having a hosepipe linked to a self replenishing water vessel. Problems of possible leakage could be overcome with a slightly more elaborate design, such as the one shown in FIG. 6. Only the relevant parts are shown, namely the attachment of the hose pipe to the cistern and the overflow as well as the attachment to the toilet pan. No 19 again indicates the cistern itself with its overflow 20. There are now two hose pipes, one within the other. The inner hose pipe 17 has the same function as in FIGS. 3 and 4. It is enclosed in an outer hose pipe 28 which is communicating with the overflow 20 through a short pipe 26 at its point of attachment to the cistern 19 either above (or as shown here) below the base of the cistern. The outer hose pipe 28 is divided from the cistern itself as well as the toilet pan. These blocked ends are marked with the number 27 in FIG. 6.

[0035] The foregoing are purely mechanical embodiments of the invention.

[0036] All of these could obviously be operated by electric motors. Electronic timing devices or mechanical systems (such as systems involving cams) can be used to optimise control of the flushing relative to the draining of the trap. Cisterns could then be dispensed with altogether and electrically controlled valves used to control the flushing. If an electric motor is used for controlling the trap the latter can be of a design not appropriate for any of the mechanical versions. One such managed trap is shown in FIG. 7.

[0037] As in FIG. 1 there is a toilet pan 1 ultimately draining into a pipe 3. The waste management coil 30 is a pipe that can rotate freely in the seals 4. Just as the version shown in FIGS. 1 and 2, it is beneficial if the path from the toilet pan to the pipe 3 is slightly downhill. To drain the trap, the waste management coil 30 is rotated around the common axis of the whole assembly. The water in the trap together with any waste matter is thereby removed on the principle of the endless screw. This makes it possible to maintain a seal against sewage gas at all times, provided the flushing of the toilet is controlled in such a way that new water is added at the time when the old water drains into the pipe 3.

[0038] It is desirable that the toilet pan is cleaned before the trap is drained. All fully mechanical versions therefore incorporate devices that initiate flushing as soon as the user begins to drain the trap. To illustrate the principles of the various designs the mechanically most simple versions have been drawn. In all mechanical versions it would be preferable to have a slightly more complicated trigger mechanism. This is because in the simple versions shown the user does not just initiate the draining of the trap but has some control over its timing. When toilets are used by children, this involves the risk that they will not just pull levers or pans but hold them in the trigger position until the cistern is empty. In that case the seal against sewage gas is not reestablished.

[0039] Electrical operation does not involve this problem at all. It would even be possible to improve on the water saving effect by having two separate flushing programs. Regardless whether there is one flushing program or two, preferably the operation would begin by releasing enough water to clean the toilet pan. Depending on the design this would be followed or accompanied by draining the trap, which in turn would be followed (or accompanied in its last stage) by the release of more water to refill the trap. In an implementation with two flushing programs these would only differ in the first stage. Where nothing more than urine is to be removed, a very small quantity of water would initially be released for cleaning the pan. The other version could either release a predetermined larger quantity of water or, up to a predetermined maximum, as much water as the user requires (until the use r's trigger action stops).

[0040]FIG. 8 illustrates another embodiment, in this version the trap management pipe 31 is immobile relative to the toilet pan 1. But it can slide into and out of the pipe 32. The trap is drained by tipping out the toilet pan and its trap management pipe. This is done by tilting up the whole mechanism, including its frame 34 around the axis 33. This slides the trap management pipe 31 into the pipe 32 against which it is sealed by the seal 35 in which it can slide freely.

[0041] The embodiment of FIG. 8 is described here for completeness. However, this embodiment is not preferred, and is in fact impracticable.

[0042] This is because hygiene dictates that the upper rim of a toilet pan should always be horizontal. Otherwise waste matter from the walls of the toilet pan can be tipped into the room as, in case of blocked pipes, can the entire contents. Moreover, as flushing has to begin as soon as one starts to tip up the toilet, water would rarely reach the upper part of the front of the toilet and could splash into the room from parts that have been raised higher than the rear of the toilet. Finally, children and physically weak people would find it unacceptably difficult to use such a toilet.

[0043] Referring now to FIGS. 9 and 10, there is described a further embodiment. FIG. 9 shows substantially the same type of toilet with sliding pan as FIG. 3. Again, pipe 3 leads to the drains. All parts of the toilet and its frame are unchanged, with a single exception at the bottom of the toilet pan. The toilet pan now terminates in a shorter section of pipe falling at a steeper angle.

[0044] Instead of managing the trap by a hose 12 there is now a short section of pipe 40 containing a permanently fixed solid object 36 that blocks the flow of water and waste matter from the toilet pan when the latter is in its rest position. The upper end of the pipe 40 and the lower end of the discharge pipe of the toilet pan are connected with an extensible hose 37 (made of rubber or some similarly elastic material), part of which is shown in greater detail in FIG. 10. The flanges 39 securely seal the connection of this hose 37 with the toilet pan 1 and the pipe 40 against water and sewer gas. The hose can expand and contract on the turtle neck principle in its section denoted with the number 38.

[0045] When the toilet is not in use the hose 37 is in firm contact with the obstacle 36, holding a small quantity of water in the toilet pan. When the toilet pan is pulled forward by one of its handles 15 a gap opens between the toilet pan's discharge pipe and the obstacle 36, allowing water and waste matter to flow through the pipes 40 and 3 to the sewers. When the toilet pan slides back the seal is automatically re-established. As the tightness of the seal depends on close contact between the obstacle 36 and the lip of the hose 37 it would be advantageous if the part of the obstacle 36 in actual contact with the lip of the hose 37 would be spherical. Preferably, the relevant part of the obstacle should be hollow, so as to give it the required flexibility to secure a tight seal.

[0046] It would obviously be possible to depart from the design described above by having a fixed connection between a fixed toilet pan and the sewers and to achieve the effect described above by having a movable obstacle inside one of the pipes near the toilet pan. This, however, would have the disadvantage that complicated moving parts would be within that part of the whole toilet system that is open to the sewers and that has water and soil flowing through it, so that the mechanism would have a greater tendency to become clogged. Furthermore, it would then be necessary to provide additional seals against sewer gas escaping through the actuating mechanism.

[0047] In comparison with the other implementations of the invention described earlier the design shown in FIG. 9 has the advantage of saving much more water. This can be seen by comparing FIGS. 3 and 9. In FIG. 3 it is necessary to have water in the bottom of the toilet pan 1 as well as part of the hose 12. In FIG. 9 only the bottom of the toilet pan needs to contain water. With appropriate dimensions the quantity of water consumed on each flush, besides that required to clean the toilet pan itself, can be reduced to significantly less than 1 liter With appropriate control over the flow of fresh water into the toilet pan this can be the only water loss when only urine is removed. Compared to some traditional toilets reductions in water consumption approaching 90% could thus be achieved.

[0048] The invention thus provides toilet arrangements which can operate in a satisfactory and hygienic manner with a low water consumption, since there is no requirement for flushing water to impart kinetic energy to floating waste.

[0049] Modifications and improvements may be made to the foregoing 

1. A toilet comprising a pan, a trap which normally retains water as a gas seal, and an outlet, wherein the trap is arranged for movement, during flushing of the toilet, in a manner which causes said retained water to transfer by gravity to the outlet.
 2. A toilet according to claim 1 in which the trap is a rigid conduit arranged for rotary or pivotal movement.
 3. A toilet as claimed in claim 1 in which the trap is constituted by a length of flexible hose.
 4. A toilet as claimed in claim 3 in which the hose normally forms a curve in which said water is retained and is arranged to be straightened during flushing by relative movement between the pan and the outlet.
 5. A toilet as claimed in claim 1 in which the trap is moved by means linked to a flushing mechanism of an associated cistern.
 6. A toilet as claimed in claim 5 in which the flushing mechanism is a conventional siphon or a bell mechanism of known type.
 7. A toilet as claimed in claim 5 in which the flushing mechanism comprises a flexible hose having a partial loop which is moved to initiate flushing.
 8. A toilet as claimed in claim 1 including means which upon initiation of flushing causes cleaning water to be supplied to the pan before or while movement of the trap commences. 